WordNet records no synonym and no antonym for repression. It is the only member of each of its synsets, which is common for technical, taxonomic and single-sense vocabulary — there is no other English word that means the same thing. The broader and narrower terms below are the useful relations in that case.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
a state of forcible subjugation
“the long repression of Christian sects”
(psychiatry) the classical defense mechanism that protects you from impulses or ideas that would cause anxiety by preventing them from becoming conscious
Synonyms, antonyms and the broader and narrower relations for repression come from Princeton University’s WordNet. Full sources and licences.
the act of repressing; control by holding down
“his goal was the repression of insolence”